491680669 has 4 divisors (see below), whose sum is σ = 495218080. Its totient is φ = 488143260.

The previous prime is 491680667. The next prime is 491680687. The reversal of 491680669 is 966086194.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 491680669 - 2¹ = 491680667 is a prime.

It is a super-2 number, since 2×491680669² = 483499760536575122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491680667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1768497 + ... + 1768774.

It is an arithmetic number, because the mean of its divisors is an integer number (123804520).

Almost surely, 2^491680669 is an apocalyptic number.

It is an amenable number.

491680669 is a deficient number, since it is larger than the sum of its proper divisors (3537411).

491680669 is a wasteful number, since it uses less digits than its factorization.

491680669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3537410.

The product of its (nonzero) digits is 559872, while the sum is 49.

The square root of 491680669 is about 22173.8735677824. The cubic root of 491680669 is about 789.2738448319.

The spelling of 491680669 in words is "four hundred ninety-one million, six hundred eighty thousand, six hundred sixty-nine".